The Bourne Identity star has shed his locks for upcoming sci-fi thriller Elysium, while his friend Gyllenhaal is also sporting less hair.

But Damon has revealed he hates his new image being compared to Gyllenhaal's appearance.

He tells People.com, "Wow, I try not to envy, but I have to say Jake's got a damn good-looking head. He sure does have a beautiful round head.

"Normally you say, 'That's a beautiful head of hair, but that's a beautiful head he's got.' Gyllenhaal definitely gets the blue ribbon for the best bald head over me."

But Damon is slowly getting used to his new look, and is pleased his wife still finds him attractive without his trademark locks: "It's really liberating. I get out of the shower and just run the towel over my head and I'm done.

"But the only problem for me was during the summer time. I had to remember to put on sunscreen. I'm not used to that. A friend of mine who is bald told me you only make that mistake once. He was right about that.

"Thank God (my wife) does (still find me attractive), but you know she had to take a whole vow, for better or for worse, so she's kind of stuck with me!"